Design Engine
Training Classes/Tutorials for Designers, Engineers, & 3D Professionals



June 29th, 2017

Plastic Part Design for Injection Molding Workshop

Plastic Part Design for Injection Molding

Course Duration: 16/40 hours

Tuition: $1,000/$2,500 USD

Overview: The course material is designed to provide a working knowledge of the plastics industry through intelligent discussions and lectures. The bulk of the time in this workshop will be spent on the part design requirements imposed on the designer by the injection molding process. The instructor and course material provides a simplified and practical approach to designing with plastic materials. Participants will recognize fundamental considerations necessary for designing products with plastics with respect to the various processes and available plastics.

The one-week course is a more comprehensive look at one or more specific manufacturing process or may offer a more extensive study and usage of SolidWorks and/or Creo.  Also check out our One Week Manufacturing Class a one-week course that covers die casting and forging in addition to plastic part design.

Similar Course One Week Manufacturing Intensive , Die Casting Part Design, Mold Design for Plastic Injection.

Onsite Training: This and all Design-Engine courses are offered onsite at your facility. Call to speak to an account manager and arrange a class at 312.226.8339 today.

Prerequisites: General knowledge of SolidWorks, Creo or other 3D CAD modeler is imperative for your experience in the course.


  • Compare plastic injection process to die casting.
  • Product development and prototype.
  • Mold filling, gating and weld lines.
  • Mechanical behavior of polymers.
  • Shrinkage, warpage and part ejection.
  • Welding and adhesive bonding technology.
  • Mechanical fasteners, press and, snap fits.
  • FEA, design recommendations, and flow mold analysis software.
  • Learn to design injection molded undercuts.
  • Learn about various plastics and their material characteristics.
  • Engineers will learn to utilize tooling and injection molders as a resource to design better parts.
  • Learn about the metal mold itself and many of its intricacies such as sleeve ejection and how it is cooled, sprue and runner, ejector bars, ejector plats, and ejector pins.


  • History of plastics.
  • How an injection mold functions in detail. This includes mold fill short shots and cooling.
  • How China plays a major role in injection molding. Discuss the quotation process for tooling and discuss partnering with local injection molders vs outsourcing. Discuss strengths and weaknesses of outsourcing.
  • Discuss basic design elements in plastic part design. Holes, ribs, thin wall features, bosses, nominal walls, and fill.
  • Discuss general rules for hollow boss design and discuss best practices. Learn about thin steel or thin blade areas and discuss ways to avoid.togo600
  • Discuss multiple plastic processes with respect to injection molds, vacuum formed parts, steel tooling, processing factors, nominal walls, radii & draft angles, ribs, weldlines, stress, cooling plastics, bosses, and undercuts.
  • Discuss gating and discuss problems such as fill vent and eject issues as related to. Also discuss how to design in solutions to possible cosmetic problems.
  • Glass filled and co-injection process and associated problems. Discussion will include teaching ways to add structural integrity to glass filled parts by aligning glass filler.
  • Sink marks and how to avoid using relations in parametric software.
  • Cooling time as related to thick sections of plastic. Internal voids and fundamentals of other problems that occur from improper piece part design.
  • Use parametric modelers and examples where using variables with a parametric modeler can save problems in the future with examples in your favorite parametric modeler.
  • FEA and stress associated with plastic piece part design with respect to FEA. Keeping in mind the deliverable for FEA is simply to make design recommendations discuss the possible solutions to many of the common molding problems. Keep in mind shrink and stress from sharp corners as related to cavity filling.
  • List plastic vendors and discuss their role and how designers can leverage their experience.
  • Discuss the Society of Plastics Engineers and their significance in the industry.
  • Discuss tooling and different materials for mold design. Discuss from a machining point of view and compare to cutting graphite for electrode burning of steel.
  • How to improve flow of the plastic through the mold and discuss Flow Molding analysis software.
  • Design undercuts and discuss advantages and disadvantages as relative to costs.
  • General disclaimers on drawings such as “brake all sharp corners”.
  • Different types of undercuts and side pull options (can be customized if prearranged with CAD manager of your various company).
  • Discuss what challenges (flow, cooling, ejection, handling, maintenance, etc) a mold designer faces when designing a mold and briefly describe in detail using your favorite parametric software an example for creating the cavity and splitting apart the mold base.
  • Draft as related to surface texture kits. Discuss how to call out textures on your favorite drawing program with examples.taskchair601
  • List 10 different plastics discuss their material characteristics.
  • Learn about relatively new plastics processes such as gas assist.

Discussions With Respect To SolidWorks and/or Creo:

  • Draft in its many forms complete with examples of Split, Draft, etc.
  • Light surfacing and its use with plastic part design.
  • Discuss top down design with examples.
  • Add Draft to parts that currently have no Draft.
  • Discuss making parts that others created.
  • Tips tricks and techniques for starting and completing plastic parts using Pro/Engineer.
  • Learn to use parameters to drive geometry relative to nominal wall thickness.
  • B-Side geometry creation techniques including PEM inserts, bosses, and ribs.
  • Utilize Draft check correctly.

injection mold tool


Introduction to Plastic Part design using your favorite constraint based modeling software. Focus on history thru best practices & making changes. This training course is developed for new and seasoned users who want to become proficient with plastic part design all in two days. We help you learn not read to you from an exercise. In this course we help design engineers learn how to make changes quickly to set them up for becoming expert faster. As with all Design-Engine classes, participants keep the training material login and password for life


This class is the same as our others in the respect that all participants will be able to access password protected HTML training materials for later use after the workshop.


“Plastic Part Design”, “Plastics Design”, “Manufacturing Part Design”, “Design for Manufacturing”, “Design for Maneuverability”, “Creo Plastic Design”


Video Training Delivery System:

Ask your Design Engine account manager about the Design-Engine Video Training Delivery System or TDS for short. We have prepared this entire class in an easy to follow guide for designers and engineers who may want this TDS as a supplement to this course. Call today to speak to an account manager about the details 312.226.8339

*Please note that prices listed on this page are based upon pre-payment prior to the start of the class and does not include the Design-engine Video training Delivery System. The TDS is available as an additional cost to this course. Call for details 312.226.8339

About the Author

Bart Brejcha
As the main instructor for Design-engine Bart teaches many of the PTC Creo & the Solidworks Surfacing classes. When he is not developing new training material you will find him on motorcycles, bicycles or on a skateboard. He loves any kind of racing on two wheels.

Design Engine Industrial Design Training Pro Engineer


Die-Casting — an Overview

(Above image courtesy of Metal Technologies) Die Casting is a process in which molten metal is forced under high pressure into a mold cavity. The molten metal is is forced into a split metal die. Certain metals are cast in a ...
by Bart Brejcha


Sketching — Another Way for Engineers to Communicate Ideas

                    Engineers need to possess many skills, most of which being technical, however, especially for engineering design, creativity is also required. In order to in...
by Bart Brejcha


“The Future of Work is Learning” – Heather McGowan

Automation and Artificial Intelligence are words that are used interchangeably but are very different. Automation is defined as “automatically controlled operation of an apparatus, process, or system by mechanical or elec...
by Bart Brejcha



2018 Chicago Auto show

I was fortunate to be able to attend the Chicago auto show media preview days. With that, photographers were able to walk through the floors and take pictures of the vehicles without fighting through crowds or taking dozens of ...
by Bart Brejcha

The StarWars BB8 replica

Bridging the Gap: Bridgewater Studio Brings Fantasy to Reality

Let me just start by saying, this place is awesome! Selfishly, I had wanted to set up a tour to play with their awesome BB8 replica as the nerdery is strong with me, but when I visited Bridgewater Studios I got much more than I...
by Bart Brejcha



Be the first to comment!

You must be logged in to post a comment.